Efficient remediation of 2,4-dichlorophenol from aqueous solution using β-cyclodextrin-based submicron polymeric particles

The water contamination by 2,4-dichlorophenol (2,4-DCP) is a tough environmental problem, so its removal has aroused much attention recently. In this study, the synthesis of a β-cyclodextrin-based submicron polymeric particles (CSPs) is described along with its utilization as adsorbent for the remediation of 2,4-dichlorophenol (2,4-DCP) from aqueous solution. Morphology and structural characterization illustrated the microstructure evolution of the aggregated CSPs with different catalytic doses. Using CSPs obtained under optimum conditions as sorbent, the adsorption performance for 2,4-DCP was systematically studied. The adsorption process fitted well the pseudo-second-order model and the Freundlich model, and thermodynamic studies manifested that the adsorption was a spontaneous and exothermic process. The slightly acidic and neutral pH as well as inorganic ions co-existence were found to be favorable for adsorption of 2,4-DCP onto CSPs. Further, CSPs had superior affinity for 2,4-DCP from aqueous media containing other analogues (2-chlorophenol and phenol). The comprehensive analysis of experimental and theoretical results suggested that the π–π, hydrophobic, and hydrogen bonding interactions may jointly drive the uptake process of 2,4-DCP. Thus, CSPs even with low surface-area showed high adsorption capacity for 2,4-DCP compared with activated carbon and other adsorbents. Also, CSPs displayed excellent structural stability and reversibility after 5 cycles of adsorption experiments. Considering the simple fabrication method employed, excellent 2,4-DCP adsorption capacity, remarkable structural stability, and reusability, CSPs provided an alternative platform for the remediation of 2,4-DCP from aqueous solution.